Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All data (experiment and calculated) in the CCCBDB for HCCH^- (acetylene anion)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K
	Enthalpy 0K
	Energy 0K		1143
	Energy 298.15K		640
	Atomization Enthalpy 298.15K		0
	Atomization Enthalpy 0K		0
	Entropy (298.15K)		0
	Entropy at any temperature		0
	Integrated Heat Capacity		0
	Heat Capacity (Cp)		0
	Nuclear Repulsion Energy		1101
	HOMO-LUMO Energies		993
	Barriers to Internal Rotation		0
Geometries	Cartesians		1046
	Internal Coordinates		1046
	Products of moments of inertia		1133
	Rotational Constants		1149
	Point Group		1153
Vibrations	Vibrational Frequencies		1149
	Vibrational Intensities		1003
	Zero-point energies		1149
	Vibrational scaling factors
	Anharmonic frequencies and constants
	Raman frequencies and intensities		9
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		674
	Dipole		866
	Quadrupole		735
	Polarizability		642
Other results	Spin		1150
	Number of basis functions		167
	Conformations		3	x